1. Technical Field
The present invention relates to a device which travels on railroad track rails and removes metallic objects, such as railroad spikes, from a railway bed. More particularly, the invention relates to such a device which has a conveyor belt for transporting the metallic objects from adjacent the railway bed into containers. Specifically, the invention relates to such a device which is configured to facilitate removal of worn conveyor belts and installation of new conveyor belts.
2. Background Information
In the railway industry, railroad track is constantly being repaired or replaced. One result of this work is the accumulation of metallic objects such as railroad spikes along the railway bed. Due to the large number of spikes and other metallic objects used, the railway bed which repair workers traverse daily may easily be littered with thousands of used spikes and other metallic objects which need to be removed. Cars or retrievers which ride on railroad track rails have been developed to facilitate the removal of these spikes and other metallic objects. The metallic objects are picked up magnetically and carried on a conveyor belt to hoppers on the car for transport to a location where they can be removed from the hoppers and recycled as scrap metal or otherwise.
One problem arising with the use of these cars is the replacement of the conveyor belts, which experience a substantial amount of wear. Typically, these conveyor belts are made of a reinforced elastomeric material which forms a loop. The replacement of the conveyor belts has been a tedious and time-consuming task. One solution involves the use of laced belts, which, however, present accelerated wear problems.
A laced belt has an elongated strip of the elastomeric material with a set of metal interlocking teeth on either end thereof so that the teeth of one set are laced together with the teeth of the other set to form the loop of the conveyor belt. To replace these belts, the two sets of teeth are disengaged from one another so that the belt may be slipped out along the length the conveyor belt track. While the laced-belt solution facilitates removal and replacement, the accelerated wear problem noted above arises due to the joint between the elastomeric material and the metal teeth, which naturally creates a point of wear as the conveyor belt moves about its track.
Thus, a continuous-loop belt of reinforced elastomeric material is preferred over the lace belts because they are longer lasting. However, the continuous-loop belts must still be replaced on a regular basis and expediting this replacement eliminates substantial down time of these metal-collecting cars. The problem arising is that the continuous-loop belts must be moved laterally, that is, transverse to their length, in order to remove a worn belt from its track and install a new belt on the track. This movement has been particularly difficult because the conveyor belt assembly and various other structure interferes with this lateral movement.
For example, the prior art uses a lift (or lifts) for adjusting the height of one end of the conveyor belt. The lift either spans the conveyor belt from side to side or is otherwise situated on the removal side of the conveyor belt so that the lift or a portion thereof must be removed from the conveyor belt assembly or other supporting structure to permit removal or installation of a belt. Another interfering factor is the structure about which the conveyor belt assembly pivots in order for the above-noted lift to raise one end of the conveyor belt assembly. The prior art pivot structure is disposed external to the loop of the conveyor belt at the exit end of the belt, which is adjacent the hopper into which metal objects are conveyed. As such, the pivot structure also spans the conveyor belt and is attached to both sides of the belt assembly so as to prevent removal and installation of a belt absent removal of the pivot structure from the belt assembly. Further, these conveyor belts are typically driven by a motorized roller disposed within the conveyor belt loop and in frictional engagement with the belt. The motor driving this drive roller is typically hydraulic and so requires hydraulic pressure and return lines between the motor and a hydraulic pump. The prior art hydraulic lines are also situated external to the conveyor belt loop so that they too interfere with removal and installation of the belt unless the lines are disconnected. The present invention provides a solution to these problems and greatly simplifies conveyor belt removal and installation.